But who are these new characters, and how do they tie in to the existing political machinations of House of Cards?

Find out everything you need to know below.

Annette Shepherd – played by Diane Lane

Anette Shepherd (Diane Lane) in House of Cards season six (Netflix)

Who is Annette Shepherd? A former school ‘friend’ of Claire’s, Annette and the President go way back. That shared history has its advantages too, now that they are two of the most powerful women in America.

Claire’s power is obvious, but what influence does Annette have? Well, she along with her brother Bill run Shepherd Unlimited, a hugely powerful conglomerate that for years has worked behind the scenes to shape and influence US policy.

Annette is the company’s public face – her brother Bill prefers to work in the shadows of sumptuous hotels and Washington corridors. Annette, like Claire, is a widow, and her cool charm makes her a worthy match for the President. However, as their priorities divide she could yet prove a dangerous enemy.

“I had a friend who said to me, ‘So are you a bad guy or good guy on the show?'” star Diane Lane told Vanity Fair when discussing her character. “There’s no such thing as any ‘good ones’ on this show because everybody’s clambering for power. And nakedly so – it’s delicious in its nakedness while remaining very astute about law, how it works, how we got where we are, holding up a mirror to things we wish were not true.”

Who plays Annette Shepherd in House of Cards? Oscar-nominated actress Diane Lane becomes the latest formidable actress to join the Netflix series, joining the likes of Robin Wright and Patricia Clarkson in season six. Her 2002 starring role in thriller Unfaithful earned her Academy Award, Golden Globe, and Screen Actors Guild Award nominations for Best Actress. She’s also starred in movies including The Outsiders, Under the Tuscan Sun and Trumbo, and this year also features in Matthew Weiner’s The Romanoffs on Amazon Prime Video.

But here’s the second part of the quote: “The Bill Shepherds of the world who won’t let go, have to go.”

Bill Shepherd, brother of Annette, scathing billionaire behind Shepherd Unlimited: at the start of season six he appears to embody everything that Claire is attempting to unpick during her presidency.

While Annette presses the flesh at fundraisers and functions, Bill prefers to keep out of the limelight if possible. But like Raymond Tusk before him, he is ruthless when it comes to playing politics to suit his business needs. Given how powerful the Shepherds are, it’s slightly odd the show hasn’t mentioned them before, but there you go.

It transpires that Bill had struck a deal with the late Francis Underwood to fund his Foundation, and expected his ‘support’ in return. Now Francis is dead, Bill expects Claire to honour the deal. Claire, of course, isn’t interested in obediently playing along.

From securing private monopolies to obscure ambitions of harvesting data from millions of Americans, Shepherd Unlimited is a nightmare of a corporation – but is Claire Underwood really the person to bring it down?

Who plays Bill Shepherd in House of Cards? Greg Kinnear is another new addition to the House of Cards cast in season six. Landing an Oscar nomination for his role in 1997 comedy drama As Good As It Gets, the actor has been a Hollywood mainstay ever since, appearing in films including Little Miss Sunshine, You’ve Got Mail and Nurse Betty. He’s set appear in upcoming noir thriller Strange but True opposite Amy Ryan.